System and method of length preservation during bone repair

ABSTRACT

In various embodiments, an implant for interfacing with a bone structure includes a web structure including a space truss. The space truss includes two or more planar truss units having a plurality of struts joined at nodes and the web structure is configured to interface with human bone tissue. In some embodiments, a method is provided that includes accessing an intersomatic space and inserting an implant into the intersomatic space. The implant includes a web structure including a space truss. The space truss includes two or more planar truss units having a plurality of struts joined at nodes and the web structure is configured to interface with human bone tissue.

PRIORITY

This application is a continuation of U.S. patent application Ser. No.14/743,607 entitled “Implant Device Having Curved or Aced Struts”, filedJun. 18, 2015 which is a continuation of U.S. patent application Ser.No. 12/960,092 entitled “Implant System and Method,” filed Dec. 3, 2010which is a continuation of U.S. patent application Ser. No. 12/640,825,entitled “Truss Implant”, filed Dec. 17, 2009, which claims priority toU.S. Provisional Patent Application Ser. No. 61/138,707, entitled “TrussImplant”, filed Dec. 18, 2008, all of which are hereby incorporated byreference in their entirety as though fully and completely set forthherein.

BACKGROUND

1. Field of the Invention

The present invention relates generally to medical devices and, morespecifically, to implants.

2. Description of the Related Art

Implants may be used in human and/or animals to support and/or secureone or more bones. For example, implants may be used in the spine tosupport and/or replace damaged tissue between the vertebrae in thespine. Once implanted between two vertebrae, the implant may providesupport between the two vertebrae and bone growth may take place aroundand through the implant to at least partially fuse the two vertebrae forlong-term support. Implants may include relatively large rims with solidmaterial that may cover, for example, 50% of the area that interactswith the endplate. The rim may provide a contact area between theimplant and the vertebral endplates. Large rims may have severaldrawbacks. For example, large rims may impede bone growth and reduce thesize of the bone column fusing the superior and inferior vertebralbodies.

Spinal implants may include open channels through the center of thesupporting rims in a superior/inferior direction. The open channeldesign may require members of the implant that separate the rims thatinteract with the vertebral endplates to absorb the compressive forcesbetween the vertebral endplates. This may increase the pressure onsmaller areas of the vertebral endplates and may potentially lead tostress risers in the vertebral endplates. Further, while bone graftmaterial is often used in conjunction with implants to encourage bonegrowth, the open column design of implants may reduce the likelihood ofbone graft material from securing itself to the implant which couldresult in a bio-mechanical cooperation that is not conducive topromoting good fusion.

Bone graft material may be packed into the implant in a high-pressurestate to prevent bone graft material from exiting the implant whilebeing placed between the vertebral endplates. The high-pressure statemay also reduce the potential for the bone graft material loosening dueto motion between the implant and the vertebral endplates or compressiveforces experienced during settling of the implant. In addition, ahigh-pressure environment may allow the bone graft material to re-modeland fuse at greater strength. High-pressure states, however, may bedifficult to create and maintain for the bone graft material in animplant.

SUMMARY

Various embodiments of implant systems and related apparatus, andmethods of operating the same are described herein. In variousembodiments, provided is an implant for interfacing with a bonestructure includes a web structure, including a space truss, configuredto interface with human bone tissue. The space truss includes two ormore planar truss units having a plurality of struts joined at nodes.

In certain embodiments, an implant includes a web structure configuredto interface with human bone tissue. The implant includes a space trussand an external truss. The space truss includes two or more planar trussunits having a plurality of struts joined at nodes. The external trussincludes one or more planar trusses having two or more adjacent planartruss units that lie in substantially the same plane.

In some embodiments, the planar truss units include a planar triangulartruss unit having three substantially straight struts and three nodes ina triangular configuration. The space truss may include a plurality ofplanar truss units coupled to one another, wherein each of the trussunits lies in a plane that is not substantially parallel to a plane ofan adjacent truss unit that shares at least one strut.

In some embodiments, at least one strut passes through the centralportion of the implant. At least one strut may connect two or moreopposing vertices of the square shaped common truss unit. At least onestrut may connect two opposed vertices of the octahedron.

In some embodiments, the implant includes an external truss structure.The external truss structure includes one or more planar trussescomprising two or more planar truss units disposed proximate an exteriorof the space truss. The external truss structure includes at least oneof a top, a bottom, or a side portion of the web structure.

The implant may include top and bottom faces wherein at least a portionof the top and bottom faces areangled relative to one another to providelordosis. The lordosis may be configured to be greater thanapproximately four degrees. The implant further includes a top externaltruss structure portion and a bottom external truss structure portionangled relative to one another such that a thickness of an anterior or aposterior region of the implant is greater than a thickness of the otherof the anterior or the posterior region of the implant.

The web structure is configured to provide support along at least fourplanes of the implant to bear against tensile, compressive, and shearforces acting on the implant.

In some embodiments, the space truss comprises truss units forming aplurality of tetrahedrons. At least two of the plurality of tetrahedronsare coupled together via one or more struts connecting two respectivevertices on each of the two tetrahedrons. The space truss may include aplurality of tetrahedrons, and wherein at least two of the tetrahedronsshare a common truss unit to form a hexahedron. The space truss mayinclude at least five truss units forming a pyramid. At least two of thepyramids are arranged opposing one another such that they share a squareshaped common truss unit at their base to form an octahedron.

The implant may be configured for use as a spinal implant, a corpectomydevice, in a hip replacement, in a knee replacement, in a long bonereconstruction scaffold, foot and ankle implant, shoulder implant, ajoint replacement or in a cranio-maxifacial implant.

In some embodiments, the plurality of struts of the web structure have adiameter less than approximately five millimeters. In some embodiments,the struts that create the space truss comprises a biologic, growthfactor or antimicrobial coupled thereto.

The implant may include an implant body comprising one or more contactfaces configured to be disposed at or near a bony structure during use,wherein the web structure is disposed on the contact surface, andwherein the web structure includes two or more struts extending from thecontact surface, and wherein two or more of the struts define an openingconfigured to enable bone through growth through the opening.

In some embodiments, a method is provided that includes accessing anintersomatic space and inserting an implant into the intersomatic space.The implant includes a web structure that includes a space truss tointerface with human bone tissue. The space truss includes two or moreplanar truss units having a plurality of struts joined at nodes.

In certain embodiments, a method of making an implant includes storing athree-dimensional model of the implant on a storage medium, applying alayer of material to a support, moving an electron beam relative to thesupport to melt a portion of the material, wherein the electron beam ismoved in a pattern determined from the three-dimensional model of atleast a portion of the implant, and removing the implant from thesupport. The implant includes a web structure that includes a spacetruss to interface with human bone tissue. The space truss includes twoor more planar truss units having a plurality of struts joined at nodes.

In some embodiments, provided is an implant that includes an implantbody having one or more contact faces to be disposed at or near a bonystructure, and a truss structure coupled to the contact face. The trussstructure is to be disposed adjacent the bony structure during use, andincludes two or more struts extending from the contact surface, whereintwo or more of the struts define an opening to enable bone throughgrowth through the opening.

In certain embodiments, provided is a method that includes slitting atleast a portion of a bony structure to form one or more slits extendingfrom a face of the bony structure into the bony structure, and insertingat least a portion of a truss structure of an implant into at least oneof the slits. The implant includes an implant body having one or morecontact faces to be disposed at or near the bony structure and the trussstructure coupled to the contact face. The truss structure is to bedisposed adjacent the bony structure during use, and the truss structureincludes two or more struts extending from the contact surface, whereintwo or more of the struts define an opening to enable bone throughgrowth through the opening.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention may be obtained when thefollowing detailed description is considered in conjunction with thefollowing drawings, in which:

FIGS. 1A-1B illustrate views of an implant with lordosis, according toan embodiment.

FIGS. 2A-2D illustrate views of an implant without lordosis, accordingto an embodiment.

FIGS. 3A-3B illustrate a web structure formed with triangular-shapedbuilding blocks, according to an embodiment.

FIGS. 4A-4B illustrate a top structure of an internal web structure ofthe implant, according to an embodiment.

FIGS. 5A-5C illustrate progressive sectioned views of the implantshowing the internal structure of the implant, according to anembodiment.

FIG. 5D illustrates an isometric view of the implant, according to anembodiment.

FIGS. 6A-6D illustrate another configuration of the web structure,according to an embodiment.

FIG. 7A illustrates a web structure formed with two pyramids, accordingto an embodiment.

FIG. 7B illustrates a web structure formed with two heptahedrons,according to an embodiment.

FIG. 7C illustrates a web structure formed with two dodecahedrons,according to an embodiment.

FIGS. 8A-8D illustrate different web structure building blocks,according to various embodiments.

FIG. 9 illustrates a random web structure, according to an embodiment.

FIG. 10 illustrates a flowchart of a method for making an implant,according to an embodiment.

FIGS. 11A-11D illustrate various views of an implant handler, accordingto an embodiment.

FIG. 12 illustrates an implant handler gripping an implant, according toan embodiment.

FIG. 13 illustrates a flowchart of a method for implanting a spinalimplant, according to an embodiment.

FIG. 14 illustrates a knee replacement implant that includes the webstructure, according to an embodiment.

FIG. 15 illustrates a hip replacement implant that includes the webstructure, according to an embodiment.

FIG. 16 illustrates a long bone reconstruction implant that includes theweb structure, according to an embodiment.

FIG. 17 illustrates a cranio-maxifacial implant that includes the webstructure, according to an embodiment.

FIG. 18 illustrates a truss structure disposed on an implant, accordingto an embodiment.

FIG. 19 illustrates a cut made into a bony structure, according to anembodiment.

FIG. 20 illustrates a cutting member, according to an embodiment.

FIGS. 21-22 illustrate a plurality of truss structures disposed on animplant, according to an embodiment.

FIG. 23 illustrates various types of truss structures disposed on animplant, according to an embodiment.

FIG. 24 is a flowchart that illustrates a method of implanting animplant, according to an embodiment.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that the drawings and detaileddescription thereto are not intended to limit the invention to theparticular form disclosed, but on the contrary, the intention is tocover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the present invention as defined by the appendedclaims. Note, the headings are for organizational purposes only and arenot meant to be used to limit or interpret the description or claims.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIGS. 1A-1B illustrate views of implant 100, according to an embodiment.Implant 100 may be used, for example, in anterior lumbar inter-bodyfusion (ALIF) or posterior lumbar inter-body fusion (PLIF). In someembodiments, implant 100 may include a web structure 101 with one ormore trusses 102 (e.g., planar and space trusses). Implant 100 and itsweb structure 101 may be used in various types of implants for humans oranimals such as spinal implants (e.g., see FIGS. 1A-2D and 5A-6D)),corpectomy devices (e.g., see FIGS. 2C-2D), knee replacements (e.g., seeFIG. 14), hip replacements (e.g., see FIG. 15), long bone reconstructionscaffolding (e.g., see FIG. 16), and cranio-maxifacial implants (e.g.,see FIG. 17). Other implant uses are also contemplated.

As used herein a “truss” is a structure having one or more elongatestruts connected at joints referred to as nodes. Trusses may includevariants of a pratt truss, king post truss, queen post truss, town'slattice truss, planar truss, space truss, and/or a vierendeel truss(other trusses may also be used). Each unit (e.g., region having aperimeter defined by the elongate struts) may be referred to as a “trussunit.”

As used herein a “planar truss” is a truss structure where all of thestruts and nodes lie substantially within a single two-dimensionalplane. A planar truss, for example, may include one or more “trussunits” where each of the struts is a substantially straight member suchthat the entirety of the struts and the nodes of the one or more trussunits lie in substantially the same plane. A truss unit where each ofthe struts is a substantially straight member such that the entirety ofthe struts and the nodes of the truss units lie in substantially thesame plane is referred to as a “planar truss unit.”

As used herein a “space truss” is a truss having struts and nodes thatare not substantially confined in a single two-dimensional plane. Aspace truss may include two or more planar trusses (e.g., planar trussunits) wherein at least one of the two or more planar trusses lies in aplane that is not substantially parallel to a plane of at least one ormore of the other two or more planar trusses. A space truss, forexample, may include two planar truss units adjacent to one another(e.g., sharing a common strut) wherein each of the planar truss unitslie in separate planes that are angled with respect to one another(e.g., not parallel to one another).

As used herein a “triangular truss” is a structure having one or moretriangular units that are formed by three straight struts connected atjoints referred to as nodes. For example, a triangular truss may includethree straight elongate strut members that are coupled to one another atthree nodes to from a triangular shaped truss. As used herein a “planartriangular truss” is a triangular truss structure where all of thestruts and nodes lie substantially within a single two-dimensionalplane. Each triangular unit may be referred to as a “triangular trussunit.” A triangular truss unit where each of the struts is asubstantially straight member such that the entirety of the struts andthe nodes of the triangular truss units lie in substantially the sameplane is referred to as a “planar triangular truss unit.” As used hereina “triangular space truss” is a space truss including one or moretriangular truss units.

In various embodiments, the trusses 102 of web structure 101 may includeone or more planar truss units (e.g., planar triangular truss units)constructed with straight or curved/arched members (e.g., struts)connected at various nodes. In some embodiments, the trusses 102 may bemicro-trusses. A “micro-truss” may include a truss having dimensionssufficiently small enough such that a plurality of micro-trusses can beassembled or other wise coupled to one another to form a web structurehaving a small enough overall dimension (e.g., height, length and width)such that substantially all of the web structure can be inserted into animplant location (e.g., between two vertebra). Such a web structure andits micro-trusses can thus be employed to receive and distributethroughout the web structure loading forces of the surrounding tissue(e.g., vertebra, bone, or the like). In one embodiment, the diameters ofthe struts forming the micro-truss may be between about 0.25 millimeters(mm) and 5 mm in diameter (e.g., a diameter of about 0.25 mm, 0.5 mm,0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm). In oneembodiment, a micro-truss may have an overall length or width of lessthan about 1 inch (e.g., a length less than about 0.9 in, 0.8 in, 0.7in, 0.6 in, 0.5 in, 0.4 in, 0.3 in, 0.2 in, 0.1 in).

As depicted, for example, in FIGS. 1A-1B, web structure 101 may extendthroughout implant 100 (including the central portion of implant 100) toprovide support throughout implant 100. Trusses 102 of implant 100 maythus support implant 100 against tensile, compressive, and shear forces.The web structure of trusses 102 may also reinforce implant 100 alongmultiple planes. The external truss structure may, for example, providesupport against tensile and compressive forces acting vertically throughthe implant, and the internal web structure may provide support againsttensile, compressive, and shear forces along the various planescontaining the respective trusses. In some embodiments, the webstructure includes trusses 102 that form a triangulated web structurewith multiple struts (e.g., struts 103 a-f) (struts are generallyreferred to herein as “struts 103”).

In one embodiment, web structure 101 of the implant 100 may include aninternal web structure that is at least partially enclosed by anexternal truss structure. For example, in one embodiment, web structure101 may include an internal web structure that includes a space trusshaving at least a portion of the space truss surrounded by an externaltruss structure that includes one or more planar trusses formed with aplurality of planar truss units that lie substantially in a singleplane. FIG. 1A depicts an embodiment of implant 100 and web structure101 that includes internal web structure 104 and an external trussstructure 105. In the illustrated embodiment, internal web structure 104includes a space truss defined by a plurality of planar truss units 106coupled at an angle with respect to one another such that each adjacenttruss unit is not co-planar with each adjacent truss units. Adjacenttruss units may include two truss units that share a strut and therespective two nodes at the ends of the shared strut.

In one embodiment, external truss structure 105 includes a plurality ofplanar trusses that are coupled about an exterior, interior or otherportion of the implant. For example, in the illustrated embodiment, theexternal truss structure 105 includes a series of planar trusses 107 a,bthat are coupled to one another. Each planar truss 107 a,b includes aplurality of planar truss units 108 that are coupled to one another andlie substantially in the same plane. As depicted, planar truss 107 aincludes four triangular planar truss units 108 having a common vertex110 and arranged to form a generally rectangular structure that lies ina single common plane 109. In other words, the four truss units arearranged to form a substantially rectangular structure having “X” shapedstruts extend from one corner of the rectangular structure to theopposite corner of the rectangular structure. As depicted, thesubstantially rectangular structure may include a trapezoidal shape. Asdescribed in more detail below, the trapezoidal shape may be conduciveto providing an implant including lordosis. Lordosis may include anangled orientation of surfaces (e.g., top and bottom) of an implant thatprovides for differences in thickness in anterior and posterior regionsof the implant such that the implant is conducive for supporting thecurvature of a vertebral column.

In one embodiment, the planar trusses that form the external truss arecoupled to one another, and are aligned along at least one axis. Forexample, in FIG. 1A, planar truss section 107 a is coupled to anadjacent planar truss 107 b. Planer truss sections 107 a,b are notparallel in all directions. Planar truss sections 107 a,b are, however,arranged parallel to one another in at least one direction (e.g., thevertical direction between the top and the bottom faces of implant 100).For example, planar trusses 107 a,b and the additional planar trussesare arranged in series with an angle relative to one another to form agenerally circular or polygon shaped enclosure having substantiallyvertical walls defined by the planar trusses and the planar truss unitsarranged in the vertical direction.

In one embodiment, the external truss portion may encompass the sides,top, and/or bottom of the implant. For example, in one embodiment, theexternal truss portion may include a top region, side regions, and/or abottom region. FIG. 1A depicts an embodiment of implant 100 whereinexternal truss portion 105 includes a top 111, bottom 112 and a sideregion 113. As described above, side region 113 includes a series ofplanar trusses arranged vertically to form a circular/polygon ring-likestructure that completely or at least partially surrounds the perimeterof the space truss disposed in the central portion of implant 100. Inthe depicted embodiment, top portion 111 of external truss structure 105includes a plurality of truss units coupled to one another to form aplanar truss that cover substantially all of the top region of internalweb structure 104. In the illustrated embodiment, the top portion 111spans entirely the region between top edges of the side portion 113 ofexternal truss structure 105. In the illustrated embodiment, top portion111 is formed from a single planar truss that includes a plurality oftruss units that lie in substantially the same plane. In other words,the planar truss of top portion 111 defines a generally flat surface.Although difficult to view in FIG. 1, the underside of implant 100 mayinclude the bottom portion 112 having a configuration similar to that ofthe top portion 111. In other embodiments, external truss structure 105may include a partial side, top and/or bottom external truss portions.Or may not include one or more of the side, top and bottom externaltruss portions. For example, as described in more detail below, FIG. 2Cdepicts an embodiment of implant 100 than includes an internal webstructure 104 that includes a space truss, and does not have an externaltruss structure.

In some embodiments, implant 100 may include a biocompatible materialsuch as a titanium alloy (e.g., γTitanium Aluminides), cobalt, chromium,stainless steel, Polyetheretherketone (PEEK), ceramics, etc. Othermaterials are also contemplated. In some embodiments, implant 100 may bemade through a rapid prototyping process (e.g., electron beam melting(EBM) process) as further described below. Other processes are alsopossible (e.g., injection molding, casting, sintering, selective lasersintering (SLS), Direct Metal Laser Sintering (DMLS), etc). SLS mayinclude laser-sintering of high-performance polymers such as thatprovided by EOS of North America, Inc., headquartered in Novi, Mich.,U.S.A. High-performance polymers may include various forms of PEEK(e.g., HP3 having a tensile strength of up to about 95 mega Pascal (MPa)and a Young's modulus of up to about 4400 MPa and continuous operatingtemperature between about 180° C. (356° F.) and 260° C. (500° F.)).Other materials may include PA 12 and PA 11 provided by EOS of NorthAmerica, Inc.

As described above, in some embodiments the trusses may form atriangulated web structure with multiple struts 103. The web structuremay include a pattern of geometrical building blocks. In someembodiments, the geometrical building blocks may include triangles. Insome embodiments, the geometrical building blocks may includepolyhedrons such as tetrahedrons (e.g., see tetrahedrons 300 a,b in FIG.3), pentahedrons, hexahedrons, heptahedrons (e.g., see heptahedron 801in FIG. 8A) and pyramids (e.g., see pyramids 705 a,b in FIG. 7A),heptahedrons 705 a,b in FIG. 7B), octahedrons (e.g., see octahedron 803in FIG. 8B), dodecahedrons (e.g., see dodecahedrons 700 a,b in FIG. 7C),and icosahedrons (e.g., see icosahedron 805 in FIG. 8C). Othergeometrical building blocks are also contemplated (e.g., sphericalfullerenes 807 in FIG. 8D). In some embodiments, such as those describedabove, the space truss of the web structure may connect multiplemidpoints of tetrahedron building blocks and include a regular patternof tetrahedron blocks arranged adjacent one another. In someembodiments, the web structure may not include a pattern of geometricalbuilding blocks. For example, FIG. 9 illustrates an irregular pattern ofstruts 103 that may be used in implant 100. Other web structures arealso contemplated.

FIGS. 3A-3B illustrate a web structure formed with triangular-shapedbuilding blocks, according to an embodiment. The triangular shapedbuilding blocks may form tetrahedrons 300 a,b that may also be used asbuilding blocks (other patterns from the triangles are alsocontemplated). Other building blocks are also contemplated (e.g.,square-shaped building blocks). In some embodiments, a web structure mayinclude a single tetrahedron, such as tetrahedron 300 a or 300 b aloneor in combination with one or more other web structures. In someembodiments, web structure 313 may include two or more tetrahedrons 300a,b. Tetrahedron 300 a may include four triangular faces in which threeof the four triangles meet at each vertex. In some embodiments, twotetrahedrons 300 a and 300 b may be placed together at two adjacentfaces to form web structure 313 with a hexahedron-shaped frame(including six faces). Hexahedron-shaped web structure 313 may includefirst vertex 301, second vertex 309, third vertex 303, fourth vertex305, and fifth vertex 307. Common plane 311 may be shared by twotetrahedrons (e.g., common plane 311 may include third vertex 303,fourth vertex 305, and fifth vertex 307) to form a hexahedron with firstvertex 301 and second vertex 309 spaced away from common plane 311. Asdepicted, the center portion of the triangular shaped building blocksmay have a void region in their center that does not include anyadditional members (e.g., no members other than the struts forming thetriangular shaped building blocks) extending there through.

As seen in FIG. 3B, in some embodiments, multiple hexahedron-shaped webstructures 313 may be arranged in a side-by-side manner. Two webstructures 313 of implant 100 may be connected via their first vertices301 a,b through strut 103 r and connected via their second vertices 309a,b through strut 103 t. Similarly, two web structures 313 may beconnected via their first vertices 301 c,d through strut 103 p andconnected via their second vertices 309 c,d through strut 103 s. Otherconnections are also possible. For example, web structures 313 mayconnect directly through side vertices (e.g., directly throughcorresponding vertices (such as vertices 303 a,b) and/or share a commonstrut (such as strut 103 u)) and/or through a side face (e.g., sidefaces 111 a,b). Other struts are also shown (e.g., struts 103 v, 103 w).

FIG. 4A illustrates additional struts 103 (e.g., struts 103 p and 103 r)connecting the first vertices (represented respectively by 301 a, 301 b,301 c, and 301 d) of four hexahedron-shaped web structures 313 inimplant 100. FIG. 4B illustrates additional struts 103 (e.g., struts 103s and 103 t) connecting second vertices 309 (represented respectively by309 a, 309 b, 309 c, and 309 d) of four hexahedron-shaped web structures313 in implant 100. In some embodiments, additional struts 103 may alsobe used internally between one or more vertices of the web structures toform additional trusses (e.g., see web structures in FIGS. 1A-2B) (otherstructures are also possible).

In some embodiments, top surface 115 a and bottom surface 115 b ofimplant 100 may include triangles, squares, circles or other shapes(e.g., a random or custom design). Top and bottom surfaces 115 a,b maybe used to connect the top and bottom vertices of various geometricalbuilding blocks used in the web structure of implant 100. For example,each vertex may be connected through struts to the neighboring verticesof other geometrical building blocks. Top surface 115 a may includeother strut networks and/or connections. In some embodiments, bottomsurface 115 b may mirror the top surface (and/or have other designs). Insome embodiments, top surface 115 a and bottom surface 115 b may engagerespective surfaces of two adjacent vertebrae when implant 100 isimplanted.

As depicted in FIG. 1B, implant 100 may include lordosis (e.g., an anglein top and/or bottom surfaces 115 a,b approximately in a range of 4 to15 degrees (such as 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15degrees)) to further support the adjacent vertebrae when implanted. Asdescribed above, lordosis may include an angled orientation of surfaces(e.g., top and bottom) that provide for differences in thickness in theanterior and posterior portions of the implant such that the implant isconducive for supporting the curvature of a vertebral column. In theillustrated embodiment, the thickness of implant 100 is greater at ornear the anterior portion 118 and lesser at or near the posteriorportion 120 of the implant. In the illustrated embodiment, the sideportions of external truss structure 105 are arranged substantiallyvertically, and the lordosis is formed by the angles of the top portion111 and bottom portion 112 of external truss structure 105. For example,in the illustrated embodiment, top portion 111 and bottom portion 112 ofexternal truss structure 105 are not perpendicular to the vertical planedefined by the side portion 113. Rather, the top portion 111 and bottomportion 112 are arranged with an acute angle relative to the verticalplane of side portion 113 at or near the anterior region 118 of implant100 and with an obtuse angle relative to the vertical plane of sideportion 113 at or near posterior region 120 of implant 100. As depicted,the vertical struts 103 that form the planar truss of side portion 113of external truss structure 105 proximate posterior region 120 ofimplant 100 are shorter than struts 103 that form side portion 113 ofexternal truss structure 105 proximate anterior region 118 of implant100. In the illustrated embodiment, in which the vertical trusses 103are substantially evenly spaced, the struts 103 forming the “X” crossmembers of the side planar trusses proximate the posterior region 120 ofimplant 100 are shorter than struts forming the “X” cross members of theside planar trusses proximate the anterior region 118 of implant 100.Other embodiments may include variations in the arrangement of thetrusses to provide various configurations of the implant. For example,in some embodiments only one or neither of the top and bottom externaltruss portions may be non-perpendicular to the side portions of theexternal truss proximate the anterior and posterior portions of theimplant. Further, the side, top, and/or bottom portions may includemultiple planar trusses angled relative to one another in anyorientation. For example, the top or bottom portions may include fourplanar trusses, each formed of multiple truss units, such that theportion(s) includes a pyramidal like shape.

In some embodiments, the implant may not include lordosis. For example,FIGS. 2A-2B illustrate two views of an embodiment of an implant 200without lordosis. In some embodiments, the top surface and bottomsurface may not include connecting struts. For example, FIGS. 2C-2Dillustrate two views of implant 250 without outer struts (e.g., withoutexternal truss portions formed of planar trusses). In the illustratedembodiment, implant 250 includes internal web structure 104 (e.g., aspace truss) and does not include an external truss structure. Forexample, in the illustrated embodiment, the exterior faces of implant250 are defined by a plurality of truss units that are angled relativeto each of its adjacent truss units. The relative alignment of the trussunits results in a non-planar exterior that includes a plurality ofpointed junctions. The pointed junctions (e.g., pointed junction 201)may operate to dig into the surrounding bone to hold the implant inplace (for example, if the implant is being used in a corpectomydevice).

FIGS. 5A-5C illustrate progressive sectioned views of implant 100showing the internal structure of implant 100, according to anembodiment. FIG. 5A illustrates a sectioned view of a lower portion ofimplant 100. Bottom surface 115 b is shown with various struts (e.g.,struts 103) extending upward from bottom surface 115 b. FIG. 5Billustrates a sectioned view approximately mid-way through implant 100.Struts, such as struts 103 e-f, shared by various stacked tetrahedronsin the web structure are shown. Some struts extend through centralportion 501 a and/or 501 b of implant 100. FIG. 5B also shows centralportions 501 a,b of implant 100. In some embodiments, central portion501 a may include a rectangular region that has a width of approximately50% of the implant width, a height of approximately 50% of the implantheight, and a length of approximately 50% of the implant length andlocated in the center of implant 100. In some embodiments, centralportion 501 b may encompass a region (e.g., a spherical region, squareregion, etc.) of approximately a radius of approximately ⅛ to ¼ of thewidth of implant 100 around a position located approximately at one halfthe width, approximately one half the length, and approximately one-halfthe height of implant 100 (i.e., the center of implant 100). Othercentral portions are also contemplated. For example, the central portionmay include a square region with a length of one of the sides of thesquare region approximately ¼ to ½ the width of implant 100 around aposition approximately at one half the width, approximately one half thelength, and approximately one half the height of the implant. An exampleheight 502 a, width 502 b, and length 502 c, is shown in FIG. 5D. Insome embodiments, the height may be up to about 75 mm or more. In someembodiments, such as those used for long bone reconstruction, the widthand/or length could be approximately 7 inches or longer. In someembodiments, the width, length, and/or height may vary along implant 100(e.g., the height may vary if the implant includes lordosis). The heightmay be taken at one of the opposing sides, the middle, and/or may be anaverage of one or more heights along the length of implant 100. The webstructure may extend through central portion 501 a,b of the implant(e.g., at least one strut of the web structure may pass at leastpartially through central portion 501 a,b). FIG. 5C illustrates anothersectioned view showing sectioned views of top tetrahedrons in the webstructure. FIG. 5D shows a complete view of implant 100 including topsurface 115 a with vertices 301 a-d.

FIGS. 6A-6D illustrate alternate embodiments of implant 100. In someembodiments, different sections of the hexahedron-shaped geometricdesign may be used. For example, as seen in FIG. 6A, the bottom half ofthe hexahedron-shaped geometric design may be used (primarily includingthe lower tetrahedron structures). If using the bottom half of thedesign, design 600 may be expanded proportionately to have similaroverall dimensions as the hexahedron-shaped geometric design (e.g., thetetrahedrons may be expanded to approximately twice the height of thetetrahedrons in the hexahedron-shaped geometric design to give design600 a height approximately the same as the hexahedron-shaped geometricdesign). In some embodiments, design 600 may also be angled (e.g., ontop surface 601 a and/or bottom surface 601 b) to provide design 600with lordosis to, in some embodiments, have a better fit between thevertebral endplates. Top surface 601 a and/or bottom surface 601 b mayalso include struts to connect nodes of design 600 (e.g., see the strutnetwork on the top surface in FIG. 6a ). Other patterns of struts fortop surface 601 a and/or bottom surface 601 b may also be used. In someembodiments, design 600 may not include negative angles between strutsand may thus be easier to create through a casting or molding process.

FIGS. 6C-6D illustrate another alternate embodiment of implant 100. Insome embodiments, approximately the middle 40 to 60 percent of thehexahedron-shaped geometric design may be used. For example, if anoverall height of the hexahedron-shaped geometric design isapproximately 37 mm, approximately the bottom 10 mm and approximatelythe top 10 mm of the design may be removed and approximately the middle17 mm of the design may be used for the implant. Middle portion design650 may then be expanded proportionately such that the approximateheight of the expanded design may be approximately 37 mm (or a differentheight as needed). Top surface 651 a and bottom surface 651 b mayinclude a network of struts (e.g., see the struts on top surface 651 aof FIG. 6C) (other networks of struts are also contemplated). Otherportions of the design for the implant are also contemplated (e.g., thetop half of the design shown in FIG. 1A, the bottom half of the designshown in FIG. 1A, etc). Design portions may be proportionately expandedto meet specified dimensions (e.g., specified height, width, andlength). In some embodiments, the amount of struts may be reduced ormaterial in the implant may be redistributed so that some struts mayhave a larger diameter and some may have a smaller diameter (e.g., thedifferent diameters may reinforce against different directional forces).In some embodiments, a partial-design cage may be used (e.g., with halfof the web structure so that the structure includes a tetrahedron.Further, in some embodiments, the implant may include angled surfaces(e.g., an angled top surface 651 a and/or angled bottom surface 651 b)to provide lordosis for implants to be implanted between the vertebralendplates.

In some embodiments, the web structure of implant 100 may distributeforces throughout implant 100 when implanted. For example, theconnecting struts of the web structure may extend throughout the core ofimplant 100, and the interconnectivity of struts 103 may disperse thestress of compressive forces throughout implant 100 to reduce thepotential of stress risers (the distribution of forces throughoutimplant 100 may prevent concentration of stress on one or more portionsof the vertebrae that may otherwise result in damage to the vertebrae).

In some embodiments, the web structure of implant 100 (e.g., theexternal and internal struts of implant 100) may also provide surfacearea for bone graft fusion. For example, the web structure extendingthroughout implant 100 may add additional surface areas (e.g., on thesurface of the struts making up implant 100) to fuse to the bone graftmaterial and prevent bone graft material from loosening or migratingfrom implant 100. In some embodiments, the web structure may alsosupport bone in-growth. For example, when implanted, adjacent bone(e.g., adjacent vertebrae if the implant is used as a spinal implant)may grow over at least a portion of struts 103 of implant 100. The bonegrowth and engagement between the bone growth and implant 100 mayfurther stabilize implant 100. In some embodiments, the surfaces ofimplant 100 may be formed with a rough surface to assist in bonein-growth adhesion.

In some embodiments, struts 103 may have a diameter approximately in arange of about 0.025 to 5 millimeters (mm) (e.g., 1.0 mm, 1.5 mm, 3 mm,etc). Other diameters are also contemplated (e.g., greater than 5 mm).In some embodiments, the struts may have a length approximately in arange of 0.5 to 20 mm (e.g., depending on the implant size needed to,for example, fit a gap between vertebral endplates). As another example,struts may have a length approximately in a range of 30-40 mm for a hipimplant. In some embodiments, the reduced strut size of the webstructure may allow the open cells in implant 100 to facilitate bonegrowth (e.g., bone may grow through the open cells once implant 100 isimplanted in the body). Average subsidence for implants may beapproximately 1.5 mm within the first 3 weeks post op (other subsidenceis also possible (e.g., approximately between 0.5 to 2.5 mm)). A strutsize that approximately matches the subsidence (e.g., a strut size ofapproximately 1.5 mm in diameter and a subsidence of approximately 1.5mm) may result in a net 0 impedance (e.g., the bone growth growingaround the struts) after implant 100 has settled in the implantedposition. The net 0 impedance throughout the entire surface area of theimplant/vertebrae endplate interface may result in a larger fusioncolumn of bone that may result in more stable fusion. Other fusioncolumn sizes are also contemplated. The configuration of the implant 100may redistribute the metal throughout the implant 100. In someembodiments, a rim may not be included on the implant 100 (in someembodiments, a rim may be included). The resulting bone growth (e.g.,spinal column) may grow through the implant 100.

In some embodiments, greater than 50% of the interior volume of implant100 may be open. In some embodiments, greater than 60%, greater than70%, and/or greater than 80% of implant 100 may be open (e.g., 95%). Insome embodiments, the open volume may be filled with bone growthmaterial. For example, cancellous bone may be packed into anopen/internal region of implant 100.

In some embodiments, at least a portion of the surfaces of implant 100may be coated/treated with a material intend to promote bone growthand/or bone adhesion and/or an anitmicrobial agent to preventinfections. For example, in some embodiments, the surface of the struts(e.g., struts 103 forming the web structure) may be coated with abiologic and/or a bone growth factor. In some embodiments, a biologicmay include a coating, such as hydroxyapatite, bone morphaginic protein(BMP), insulinlike growth factors I and II, transforming growthfactor-beta, acidic and basic fibroblast growth factor, platelet-derivedgrowth factor, and/or similar bone growth stimulant that facilitatesgood biological fixation between the bone growth and a surface of theimplant. In some embodiments, a bone growth factor may include anaturally occurring substance capable of stimulating cellular growth,proliferation and cellular differentiation (e.g., a protein or steroidhormone).

In some embodiments, a biologic and/or growth factor may be secured to acentral region of implant 100. For example, in some embodiments, abiologic or growth factor may be provided on at least a portion of astrut that extends through central portion 501 a and/or 501 b of implant100. Such an embodiment may enable the delivery of a biologic and or agrowth factor to a central portion of an implant. For example, thebiologic or growth factor may be physically secured to a strut in acentral portion of implant 100 as opposed to being packed into an openvolume that does not include a strut provided therein for the physicalattachment of the biologic and/or growth factor.

As implant 100 settles into the implant site, subsidence may placeadditional pressure on the bone graft material (which may already beunder compressive forces in implant 100) and act to push the bone graftmaterial toward the sides of implant 100 (according to Boussinesq'stheory of adjacent material, when a force is applied to a member that isadjacent to other materials (such as sand, dirt, or bone graft material)the force against the member creates a zone of increased pressure (e.g.,60 degrees) in the adjacent material). Struts 103 of the web structuremay resist bone graft material protrusion from the sides of the webstructure and may increase the pressure of the bone graft material. Bonegraft material may need to be implanted in a higher-pressure environmentto create an environment conducive to strong bone growth (e.g.,according to Wolf's law that bone in a healthy person or animal willadapt to the loads it is placed under). The web structure may thusincrease the chance of stronger fusion.

FIG. 7A illustrates a web structure formed with two pyramids, accordingto an embodiment. The geometric building blocks for implant 100 includepyramids. For example, top/upper pyramid 705 a and bottom/lower pyramid705 b may be joined to form a octahedron building block 703. Theoctahedron building blocks 703 may be joined, for example, at a face(e.g., a base 706 of the top and bottom pyramids 705 a and 705 b) bysharing a surface, etc. In one embodiment one or both of top and bottompyramid 705 a,b may include a square pyramid. The resulting octahedronthus includes two opposing pyramid shaped truss structures that share acommon square shaped truss unit at their base (e.g., where the two basesof the pyramids meet).

It is further noted that the geometric building block may include one ormore additional struts extending through an interior region defined bythe faces of the building blocks. For example, in the illustratedembodiment, the octahedron building block formed from top and lowerpyramids 705 a,b include two struts 103 a extending diagonally betweenopposing vertices of the face (e.g., the square shaped truss unit)shared by top and lower pyramids 705 a,b, and having an intersection710. Accordingly, the opposing vertices are directly connected by one ormore struts arranged in a substantially straight line between each pairof the opposing vertices. In one embodiment, struts 103 a may be formedfrom four separate strut sections that extend from each respectivevertex to intersection 710. The illustrated embodiment also includes anadditional central strut 103 b that extends between vertices 701, 709 oftop and bottom pyramids 705 a,b, and that intersects struts 103 a at ornear intersection 710. In one embodiment, strut 103 b may be formed fromone or two separate strut sections that extend from each respectivevertex 701, 709 of top and bottom pyramids 705 a,b to intersection 710.Accordingly, the opposing vertices of the octahedron that do not lie inthe common face (e.g. base) of the two pyramids 705 a,b forming theoctahedron are directly connected by one or more struts arranged in asubstantially straight line between the opposing vertices. Otherembodiments may include any combination of struts 103 a,b. For example,one embodiment may include only one or two of struts 103 a extendingbetween opposing vertices of the square shaped common truss unit andwithout strut 103 b. For example, one embodiment may include only twoopposing vertices of the square shaped common truss unit being connectedto one another via a strut. One embodiment may include only strut 103 bextending between the opposing vertices of the octahedron without struts103 a.

FIG. 7B illustrates a web structure formed with two heptahedrons,according to an embodiment. The geometric building blocks for implant100 include heptahedrons. For example, top/upper heptahedron 705 a andbottom/lower heptahedron 705 b may be joined to form a dodecahedronbuilding block 703. The dodecahedron building blocks 703 may be joined,for example, at a face (e.g., their bases) by sharing a side surface,etc. Embodiments may include additional members, such as struts 103 a,bthat extend between vertices of the heptahedron 705 a,b in a mannersimilar to that described with respect to FIG. 7A.

FIG. 7C illustrates a web structure formed with two dodecahedrons,according to an embodiment. For example, top/upper dodecahedron 705 aand bottom/lower dodecahedron 705 b may be joined to form a 22-sidedpolyhedron building block 703. The 22-sided polyhedron building blocks703 may be joined, for example, at a face by sharing a side surface,etc. Embodiments may include additional members, such as struts 103 a,bthat extend between vertices of the dodecahedrons 705 a,b in a mannersimilar to that described with respect to FIG. 7A.

Web structures formed from other truss configurations are alsocontemplated. For example, the trusses may include a series of packingtriangles, a two-web truss, a three-web truss, etc. Further, the webstructure for implant 100 may include one or more trusses as describedin U.S. Pat. No. 6,931,812 titled “Web Structure and Method For Makingthe Same”, which issued Aug. 23, 2005, which is hereby incorporated byreference in its entirety as though fully and completely set forthherein.

FIG. 10 illustrates a flowchart of a method for making implant 100. Insome embodiments, implant 100 may be made through rapid prototyping(e.g., electron beam melting, laser sintering, etc). It should be notedthat in various embodiments of the methods described below, one or moreof the elements described may be performed concurrently, in a differentorder than shown, or may be omitted entirely. Other additional elementsmay also be performed as desired. In some embodiments, a portion or theentire method may be performed automatically by a computer system.

At 1001, a three dimensional model of implant 100 may be generated andstored in a storage medium accessible to a controller operable tocontrol the implant production process. At 1003, a layer of material(e.g., a powder, liquid, etc.) may be applied to a support. In someembodiments, the powder may include γTiAl (γTitanium Aluminides) whichmay be a high strength/low weight material. Other materials may also beused. The powder may be formed using a gas atomization process and mayinclude granules with diameters approximately in a range of 20 to 200micrometers (μm) (e.g., approximately 80 μm). The powder may bedelivered to the support through a distributer (e.g., delivered from astorage container). The distributer and/or the support may move duringdistribution to apply a layer (e.g., of powder) to the support. In someembodiments, the layer may be approximately a uniform thickness (e.g.,with an average thickness of 20 to 200 micrometers (μm)). In someembodiments, the distributer and support may not move (e.g., thematerial may be sprayed onto the support). At 1005, the controller maymove an electron beam relative to the material layer. In someembodiments, the electron beam generator may be moved, and in someembodiments the support may be moved. If the material is γTiAl, amelting temperature approximately in a range of 1200 to 1800 degreesCelsius (e.g., 1500 degrees Celsius) may be obtained between theelectron beam and the material. At 1007, between each electron beampass, additional material may be applied by the distributer. At 1009,the unmelted material may be removed and implant 100 may be cooled(e.g., using a cool inert gas). In some embodiments, the edges of theimplant may be smoothed to remove rough edges (e.g., using a diamondsander). In some embodiments, the implant may include rough edges toincrease friction between the implant and the surrounding bone toincrease adhesion of the implant to the bone.

Other methods of making implant 100 are also contemplated. For example,implant 100 may be cast or injection molded. In some embodiments,multiple parts may be cast or injection molded and joined together(e.g., through welding, melting, etc). In some embodiments, individualstruts 103 forming implant 100 may be generated separately (e.g., bycasting, injection molding, etc.) and welded together to form implant100. In some embodiments, multiple implants of different sizes may beconstructed and delivered in a kit. A medical health professional maychoose an implant (e.g., according to a needed size) during the surgery.In some embodiments, multiple implants may be used at the implant site.

FIGS. 11A-11D illustrate various views of implant handler 1100,according to an embodiment. In some embodiments, handler 1100 mayinclude jaws 1107 to grip and release implant 100. Jaws 1107 may beoperated by trigger 1109 coupled to cam 1115 that acts to push block1101 when trigger 1109 is pushed away from handle 1117. In someembodiments, leaf spring 1111 may act to push trigger 1109 away fromhandle 1117. As block 1101 is pushed by cam 1115, block 1101 may pushagainst compression spring 1103 and shaft 1105 (which may be flexibleshaft inside tube 1119). Shaft 1105 may push against jaws 1107 and pushthem open (see FIG. 11D). As trigger 1109 is pulled toward handle 1117,the force on block 1101 may be released and coil compression spring 1103may push block 1101 toward handle 1117. Shaft 1105 may also be pulledwith block 1101 toward handle 1117 (in some embodiments, shaft 1105 maybe coupled to block 1101). As shaft 1105 is pulled toward handle 1117,shaft 1105 may pull jaws 1107 closed (e.g., see FIGS. 11c and 12) suchthat struts of implant 100 may be gripped in grooves 1119 in jaws 1107(e.g., see FIG. 12 which illustrates handler 1100 gripping implant 100).In some embodiments, block 1201 (see FIG. 12) may be gripped betweenjaws 1107 and at least partially in contact with implant 100 to at leastpartially distribute forces from a hammer (used to implant the implant100) over a greater contact area on implant 100 (to prevent aconcentration of impact force on a limited number of struts). Handler1100 is one embodiment of a handler for implant 100; other handlers andhandler types are also contemplated.

FIG. 13 illustrates a flowchart of a method for implanting a spinalimplant, according to an embodiment. It should be noted that in variousembodiments of the methods described below, one or more of the elementsdescribed may be performed concurrently, in a different order thanshown, or may be omitted entirely. Other additional elements may also beperformed as desired. In some embodiments, a portion or the entiremethod may be performed automatically by a computer system.

At step 1301, an intersomatic space may be accessed. For example, ananterior opening may be made in a patient's body for an anterior lumbarinter-body fusion (ALIF) approach or a posterior opening may be made fora posterior lumbar inter-body fusion (PLIF) approach. At 1303, at leasta portion of the intersomatic space may be excised to form a cavity inthe intersomatic space. At 1305, the implant may be inserted into thecavity in the intersomatic space. In some embodiments, handler 1100 maybe used to grip implant 100. In some embodiments, force may be appliedto the implant (e.g., through a hammer) to insert the implant into thecavity. After placement of implant 100, trigger 1109 on handler 1100 maybe released to release implant 100. At 1307, before and/or afterinsertion of the implant, the implant and/or space in the cavity may bepacked with bone graft material. At 1309, the access point to theintersomatic space may be closed (e.g., using sutures).

FIG. 14 illustrates knee replacement implant 1400 that includes a webstructure, according to an embodiment. In some embodiments, portions ofknee replacement implant 1400 may include a web structure to, forexample, increase bone graft fusion with surrounding bone (e.g., alongportions of implant 1400 that are anchored in the bone). Portion 1401 aand 1401 b may include the web structure for bone in-growth to furthersupport and secure the knee implant. Other portions of knee implant 1400may also include a web structure.

FIG. 15 illustrates hip replacement implant 1500 that includes a webstructure, according to an embodiment. Portions of shaft 1501 of hipimplant 1500 may include a web structure for bone in-growth along theshaft to support and secure the hip implant 1500. In some embodiments,implant 1500 may use a web structure in place of (or in addition to)texture along shaft 1501 for securing implant 1500.

FIG. 16 illustrates long bone reconstruction implant 1600 that includesa web structure, according to an embodiment. In some embodiments, a webstructure may be used in implant 1600 for securing a long bone (e.g.,the femur or tibia). For example, if the long bone has a compoundfracture, the implant may be fastened to the bone along the bone (e.g.,using bone screws 1601) to keep the bone segments in place duringhealing. The bone may also grow into the implant web structure tofurther secure the implant to the long bone. Other bones are alsocontemplated (e.g., clavicle, phalanges, metatarsals, etc). The implantmay be coated and/or infused with a biologic material to encourage bonegrowth or an antimicrobial agent to reduce the chance of infection.

FIG. 17 illustrates cranio-maxifacial implant 1700 that includes a webstructure, according to an embodiment. In some embodiments, implant 1700may be used to reconstruct a portion of the jaw. The top and bottomsurfaces of implant 1700 may include additional struts (e.g., as seen inFIG. 1A) or may include point junctions (e.g., as seen in FIG. 2D).Implant 1700 may be secured to the implant site (e.g., through bonescrews 1701) or may be self securing (e.g., between two or more bones).

In some embodiments, the implant may be customized. For example, threedimensional measurements and/or shape of the implant may be used toconstruct an implant that distributes the web structure throughout athree-dimensional shape design. As noted in FIG. 10, thethree-dimensional shape design of the implant may be entered into acomputer system/controller that may control the electron beam meltingprocess. In some embodiments, the truss design and orientation may bepreset or predetermined by the computer system/controller. In someembodiments, a user may select the truss design to use (e.g., one ormore of truss designs shown in FIG. 3A, 7A, or 8A-9) and/or may selectthe orientation of the trusses in the implant. In some embodiments, theuser may enter the outer dimensions of the three dimensional shape andthe computer system/controller may generate a three-dimensional designthat includes the truss design and orientation. The computersystem/controller may generate the three-dimensional design by providinga uniform distribution of the truss design throughout athree-dimensional shape with the outer dimensions provided by the user.In some embodiments, the heights and widths of the trusses used in thedesign may be proportional to the overall height and width of thethree-dimensional shape (e.g., the trusses may have heightsapproximately equal to ½ the overall height and a width of approximately1/16 the overall width). Other heights and widths are also contemplated.In some embodiments, the user may provide the height and width and/orthe computer system/controller may have default heights and widths touse.

Embodiments of a subset or all (and portions or all) of the above may beimplemented by program instructions stored in a memory medium or carriermedium and executed by a processor (e.g., a processor on the controlleroperable to control the implant production process). A memory medium mayinclude any of various types of memory devices or storage devices. Theterm “memory medium” is intended to include an installation medium,e.g., a Compact Disc Read Only Memory (CD-ROM), floppy disks, or tapedevice; a computer system memory or random access memory such as DynamicRandom Access Memory (DRAM), Double Data Rate Random Access Memory (DDRRAM), Static Random Access Memory (SRAM), Extended Data Out RandomAccess Memory (EDO RAM), Rambus Random Access Memory (RAM), etc.; or anon-volatile memory such as a magnetic media, e.g., a hard drive, oroptical storage. The memory medium may comprise other types of memory aswell, or combinations thereof. In addition, the memory medium may belocated in a first computer in which the programs are executed, or maybe located in a second different computer that connects to the firstcomputer over a network, such as the Internet. In the latter instance,the second computer may provide program instructions to the firstcomputer for execution. The term “memory medium” may include two or morememory mediums that may reside in different locations, e.g., indifferent computers that are connected over a network.

In some embodiments, a computer system at a respective participantlocation may include a memory medium(s) on which one or more computerprograms or software components according to one embodiment of thepresent invention may be stored. For example, the memory medium maystore one or more programs that are executable to perform the methodsdescribed herein. The memory medium may also store operating systemsoftware, as well as other software for operation of the computersystem.

In some embodiments, a truss/web structure may be disposed on at least aportion of an implant to facilitate coupling of the implant to anadjacent structure. For example, where an implant is implanted adjacenta bony structure, one or more truss structures may be disposed on and/orextend from a surface (e.g., an interface plate) of the implant that isintended to contact, and at least partially adhere to, the bonystructure during use. In some embodiments, such as those including anintervertebral implant disposed between the end plates of two adjacentvertebrae during, one or more truss structures may be disposed on acontact surface of the intervertebral implant to facilitate bone growththat enhances coupling of the intervertebral implant to the bonystructure. For example, a truss structure may include one or more strutsthat extend from the contact surface to define an open space for bonegrowth therethrough, thereby enabling bone through growth to interlockthe bone structure and the truss structure with one another to couplethe implant to the bony structure at or near the contact face. Suchinterlocking bone through growth may inhibit movement between theimplant and the bony structure which could otherwise lead to loosening,migration, subsidence, or dislodging of the implant from the intendedposition. Similar techniques may be employed with various types ofimplants, including those intended to interface with tissue and/or bonestructures. For example, a truss structure may be employed on a contactsurface of knee implants, in a corpectomy device, in a hip replacement,in a knee replacement, in a long bone reconstruction scaffold, or in acranio-maxifacial implant hip implants, jaw implant, an implant for longbone reconstruction, foot and ankle implants, shoulder implants or otherjoint replacement implants or the like to enhance adherence of theimplant to the adjacent bony structure or tissue.

FIG. 18 depicts an embodiment of an implant 1800 in accordance with oneor more embodiments of the present technique. In some embodiments,implant 1802 may include a spinal implant, a knee implant, a hipimplant, a jaw implant, an implant for long bone reconstruction, or thelike. In one such embodiment, implant 1800 may include an intervertebralimplant that is to be implanted between end plates of two adjacentvertebras during a spinal implant procedure. For example, implant 1800may include a fusion implant (e.g., a fusion cage) intended to rigidlyfix the relative positions of the two adjacent vertebrae, or and dynamicintervertebral device intended to couple to each of the two adjacentvertebrae and to facilitate motion (e.g., flexion, extension, and/orlateral bending) between the two adjacent vertebrae.

In the illustrated embodiment, implant 1800 includes a body 1802 havingtwo contact faces 1804 a,b. As used herein, the term “contact face”refers to a portion of an implant intended to be in contact or nearcontact with an adjacent structure (e.g., a bony structure) toadhere/couple with the adjacent structure when implanted. A contactsurface may include an interface plate of an implant, for instance. Animplant may include any number of contact faces. For example an implantmay include one or more contact faces intended to couple to one or moreadjacent bony structures. As depicted, in some embodiments, contact face1804 a may include an upper contact face intended to contact and secureto a first adjacent bony structure, and 1804 b may include a lowercontact face intended to contact and secure to a second adjacent bonystructure. For example, where implant 1800 is intended to sandwichbetween two adjacent bony structures (e.g., end plates of two adjacentvertebrae), contact face 1804 a may couple to a portion of the firstbony structure disposed above implant 1800 and contact face 1804 b maycouple to the second bony structure disposed below implant 1800. It willbe appreciated that the number and orientation of the contact surfacesmay vary based on the intended application, and, thus, relative termssuch as upper and lower are intended as exemplary and are not intendedto be limiting. For example, one or both of the upper and lower contactfaces 1804 a,b may be oriented such that the are disposed laterally(e.g., as right, left, back and/or front sides of implant body 1802.Moreover, the cubic shape of body 1802 is intended to be exemplary andis not intended to be limiting. For example, body 1802 may include anydesirable implant construct such as fusion cages with different shapesor a mechanical construct that allows for motion preservation. Contactsurface(s) may take any suitable shape, e.g., a substantially flatplanar surface, a curved/contoured surface, ridges, or the like.

In some embodiments, a single, a plurality or all of the contact facesof an implant may include one or more truss structures. For example, inthe illustrated embodiment, upper contact face 1804 a includes a trussstructure 1806 disposed thereon. Such an embodiment may be of particularuse when implant 1800 is intended to create a fixation for a tibila trayand femoral component for a knee replacement implant or any other jointreplacement implant. It will be appreciated that although trussstructure 1806 is illustrated on a single contact surface, otherembodiments may include any number of truss structures disposed on anynumber of contact faces. For example, in some embodiments, implant 1800may include one or more truss structures 1806 disposed on one or both ofupper and lower contact surfaces 1804 a,b. Such an embodiment may be ofparticular use when implant 1800 is intended to span the distancebetween two adjacent bony structures (e.g., the end plates of twoadjacent vertebrae).

In some embodiments, a truss structure includes one or more struts thatextend from a respective contact surface and defines an opening thatenables bone through growth to facilitate coupling of the trussstructure and the implant to the bony structure. For example, in theillustrated embodiment, truss structure 1806 includes a space trussformed of three struts 1807 a,b,c that each include elongate memberseach having a first end coupled to contact surface 1804 a and a secondend coupled to each of the other struts at a vertex 1810. Each face ofthe triangular shaped truss structure includes a planar truss structurehaving a triangular opening with a perimeter defined by two of struts1807 a,b,c and the adjacent portion of contact face 1804 a. As depicted,truss structure 1806 includes a generally triangular shaped space trussthat defines a four sided, substantially open volume 1812.

In some embodiments, open volume 1812 may facilitate bone growth throughtruss structure 1806, thereby enhancing coupling of implant 1800 to theadjacent bony structure. For example, in some embodiments, at least aportion of truss structure 1806 is in contact or near contact with theadjacent bony structure, thereby enabling bone growth to extend intoand/or through at least a portion of open volume 1812 of truss structure1806 such that the bone growth interlocks with one or more struts 1808a,b,c of truss structure 1806. The interlocking of the bone growth andthe struts may rigidly fix implant 1800 in a fixed location relative tothe bony structure.

In some embodiments, implant 1800 may be pressed into contact with theadjacent bony structure such that at least a portion of truss structure1806 is disposed inside of the adjacent bony structure uponimplantation. For example, in some embodiments, implant 1800 may bepressed into contact with the adjacent bony structure such that vertex1810 pierces into the bony structure and is advanced such that at leasta portion of struts 1808 a,b,c and open volume 1812 extend into the bonystructure. Such a technique may encourage bone to grow into and/orthrough open volume 1812. In some embodiments, implant 1800 may beadvanced/pressed into the adjacent bony structure until the respectivecontact surface (e.g., upper contact surface 1804 a) is in contact ornear contact with the adjacent bony structure. In some embodiments, atleast a portion of the truss structure and/or the contact surface may becoated/treated with a material intend to promote bone growth and/or boneadherence and an antimicrobial to prevent infection to the trussstructure and/or the contact surface. For example, in some embodiments,the surface of the struts and/or the contact surface may be coated witha biologic and/or a bone growth factor, such as those described herein.

In some embodiments, at least a portion of the adjacent bony structurein which the truss structure is to be implanted may be pierced/cut/slitprior to truss structure 1806 being advanced/pressed into the adjacentbony structure. In some embodiments, a cutting tool/edge may be used tocut into the adjacent bony structure such that the resulting cutsaccommodate one or more struts of truss structure 1806. For example,where truss structure 1806 includes a triangular shape, such as thatdepicted in FIG. 18, one or more complementary cuts may be made into theadjacent bony structure in a complementary pattern. FIG. 19 illustratesa cut 1820 that may be made into adjacent bony structure 1822 prior toor as a result of truss structure 1806 being advanced/pressed into theadjacent bony structure 1822. FIG. 19 may be representative of an endview of a vertebra (e.g., looking upward/downward into the end plate ofthe vertebrae). In some embodiments, cut 1820 may include one or moresegments intended to accommodate one or more struts of truss structure1806. For example, in the illustrated embodiment, cut 1820 includesthree slits 1820 a,b,c formed in bony structure 1822. Slits 1820 a,b,cmay extend from the face of the bony structure into the bony structurein a direction substantially perpendicular to a face of the bonystructure and/or substantially parallel to the intended direction ofadvancement of truss structure 1806 and/or implant 1800 into the bonystructure.

In some embodiments, slits 1820 a,b,c include cuts into the bone that donot require any bony material to be removed. For example, a sharpcutting edge may be advanced into the bone to create the slit, with nosubstantial amount of bone being removed. During implantation of implant1800 into bony structure 1822, struts 1808 a,b,c may slide into slits1820 a,b,c, respectively. Although the illustrated embodiments includesthree slits oriented at approximately one-hundred twenty degreesrelative to one another about a vertex 1824, other embodiments mayinclude any number of slits in any variety of orientation to accommodateone or more struts of a truss structure extending from a contact face ofan implant. Cut 1820 may be complementary to the shape/orientation ofstruts 1808 of truss structure 1806. For example, where truss structureis substantially pyramidal in shape (e.g., see truss structure 1806 bdescribed below with respect to FIG. 23), cut 1820 may include fourslits oriented at approximately ninety-degrees relative to one another.

In some embodiments, cut 1820 may be formed by one or more complementarycutting members (e.g., knives/blades) that are pressed, slid, orotherwise advanced into bony structure 1822. In one embodiment, acutting member includes one or more cutting edges arranged complementaryto the profile of the struts of the truss structure such thatadvancement of the cutting edge cuts one, a plurality, or all of theslits to accommodate the truss structure being advanced/pressed into thebony structure.

FIG. 20 illustrates a cutting member 1830 in accordance with one or moreembodiments of the present technique. Cutting member 1830 includes threecutting blades 1830 a,b,c oriented at approximately one-hundred twentydegrees relative to one another about a vertex 1834. In someembodiments, cutting members 1830 a,b,c, are arranged complementary toslits 1820 a,b,c of cut 1820 and/or struts 1808 a,b,c of truss structure1806. Although the illustrated embodiment includes three cutting bladesoriented at approximately one-hundred twenty degrees relative to oneanother about a vertex 1834, other embodiments may include any number ofcutting blades in any variety of orientation to accommodate one or morestruts of a truss structure extending from a contact face of an implant.For example, where truss structure is substantially pyramidal in shape(e.g., see truss structure 1806 b described below with respect to FIG.23), cutting member 1830 may include four cutting blades oriented atapproximately ninety-degrees relative to one another.

In some embodiments, the cutting blades may be advanced into bonystructure 1822 at a depth that is about the same or deeper than theheight of truss structure 1806. In some embodiments, the cutting bladesmay be advanced into bony structure 1822 at a depth that is about thesame or shallower than the height of truss structure 1806. In someembodiments, a leading edge of the cutting blades may be shaped to becomplementary to the shape of the struts. For example, the leading edgeof one, a plurality, or all of cutting blades 1830 a,b,c, may be angledsimilar to the angle of struts 1808 a,b,c extending from contact surface1804 a, as illustrated by dashed line 1846.

In some embodiments, cutting member 1830 may be provided as aninstrument that is advanced into the bony structure. In someembodiments, cutting member 1830 may be integrated with or more otherdevices used during the implantation procedure. For example, during aspinal implant procedure, cutting member 1830 may be coupled to adistractor typically positioned between the vertebrae and expanded toset the relative positions of the vertebrae. The force of distractionmay act to advance the cutting member into the bony structure.

FIG. 20 illustrates a cutting member 1830 is disposed on a top surface1844 a of a body 1842 of a distractor 1840, in accordance with one ormore embodiments of the present technique. In some embodiments, one ormore cutting members may be disposed on other portions of distractor,such as a bottom surface 1844 b. During use, distractor 1840 may bedisposed between the adjacent bony structures and expanded such that topand bottom surfaces 1844 a,b move away from one another, therebypressing one or more of cutting members 1830 into the adjacent bonystructure (e.g., 1822) to form one or more cuts (e.g., 1820) in the bonystructure, where the cuts are intended to accommodate struts (e.g., 1808a,b,c) of the truss structure (e.g., e.g., 1806) of an implant (e.g.,1800) to be engaged with the bony structure. In some embodiments, thedistractor may be used to increase a separation distance between twoadjacent bony structures (e.g., between end plates of adjacentvertebrae). In some embodiments, subsequent to making the cuts, thedistractor is unexpanded and/or removed, and the implant (e.g., 1800) isdisposed between the bony structures (e.g., in substantially the sameposition as the distractor) such that one or more truss structures arealigned/engaged with one or more of the cuts.

Although several of the above embodiments have been described withregard to a single truss structure, other embodiments may include anynumber of truss structures. For example, as depicted in FIG. 21, aplurality of truss structures may be provided on one or more contactsurfaces of implant 1800. In the illustrated embodiment, four trussstructures 1806 a,b,c,d are disposed substantially adjacent one anotheron contact surface 1804 a,b of implant 1800 such that one, a plurality,or all of struts of truss structures 1806 a,b,c,d share common verticesat the contact surface 1804 a. In some embodiments, one, a plurality orall of truss structures may be spaced apart from one another. Forexample, one, a plurality, or all of truss structures 1806 a,b,c,d maynot share a vertices at or near contact surface 1804 a. In someembodiments, any number of truss structures may be provided on anyportion of implant 1800. In some embodiments, the shape and orientationof the truss structures may be varied to mimic various desired shapes.For example, in some embodiments, the truss structures may be varied inheight to provide a curved profile similar to that of a ball and/or asocket of a joint.

In some embodiments, implant 1800 may include a plurality of trussstructures stacked upon one another to form a web-like structuredisposed on one or more faces of implant 1800. FIG. 22 illustrates amulti-layer truss-structure (e.g., web structure) disposed on a contactsurface of implant 1800 in accordance with one or more embodiments ofthe present technique. In the illustrated embodiment, a triangular trussstructure 1806 e is stacked atop vertices of truss structures 1806b,c,d. In some embodiments, a truss structure provided at a contactsurface of an implant may include a web structure, such as thosedescribed with respect to implants 100, 200 250, 600 and 650 describedherein. In some embodiments, the shape and orientation of the webstructures may be varied to mimic various desired shapes. For example,in some embodiments, the web structure may be varied in height toprovide a curved profile similar to that of a ball and/or a socket of ajoint.

In some embodiments, one or more additional struts may be providedbetween one, a plurality, or all of the vertices of truss structures.For example, in the illustrated embodiment, struts 1808 d,e,f,g,h extendbetween the vertices of truss structures 1806 a,b,c,d. In someembodiments, one or more struts may extend between a plurality or all ofthe struts at or near the point where they are coupled to the contactface. For example, one or more struts may extend in place of one or moreof the dashed lines illustrated in FIGS. 18, 21, 22 and 23.

Some of the above embodiments have been described with respect to aparticular shaped truss structure (e.g., a triangular shaped space trussstructure 1806) although various shapes of truss structures arecontemplated. It will be appreciated that such description is intendedto be exemplary and is not intended to be limiting. FIG. 23 illustratesa plurality of exemplary truss structures that may be coupled to acontact face of an implant in accordance with one or more embodiments ofthe present technique.

In some embodiments, a truss structure 1806 may include atriangular-shaped planar truss. For example, truss structure 1806 aincludes two substantially shaped truss members extending from contactsurface 1804 a and coupled to one another at a vertex to define an openregion 1812 a through which bone growth may occur. Other embodiments mayinclude any variety of geometrical truss structure shapes, such asfour-sided (e.g., pyramidal), five-sided, six-sided, seven sided (notdepicted), and/or eight sided truss structures 1806 b,c,d,e,respectively. Additionally, cubic, rectangular or pentagonal blockshaped structures may be used. Moreover, embodiments may include any ofthe truss-structures disclosed herein, such as those disclosed withrespect to FIGS. 1A-9. In some embodiments, any type, size, number, orcombination of number, types and sizes of truss structures may beprovided on one, a plurality, or all of the contact faces of an implant.

FIG. 24 is a flowchart that illustrates a method 1900 of implanting animplant in accordance with one or more embodiments of the presenttechnique. In the illustrated embodiment, method 1900 includes preparinga bony structure, as depicted at block 1902, and inserting an implant(e.g., 1800), as depicted at block 1904. In some embodiments, preparinga bony structure includes positioning the bony structure. For example, adistractor (e.g., 1840) may be used to separate adjacent bony structuressuch that the implant can be sandwiched between the two adjacent bonystructures. In some embodiments, preparing a bony structure includescutting/slitting the bony structure to accommodate one or more struts ofa truss structure of an implant to be coupled to the bony structure. Forexample, a cutting member (e.g., 1830) may be advanced into the bonystructure to create a cut (e.g., 1820) including one or more slits(e.g., 1820 a,b,c). In some embodiments, distraction and cutting may beprovided simultaneously via use of a distractor that includes one ormore cutting members coupled to one or more of its contact faces (e.g.,distractor 1830 having cutting members 1830 coupled thereto).

In some embodiments, inserting the implant includes positioning theimplant (e.g., 1800) adjacent the bony structure (e.g., 1822), aligningthe truss structure (e.g., 1806) with a complementary portion of thebony structure (e.g., 1820) and/or advancing a contact surface (e.g.,1804 a,b) toward the bony structure such that at least the trussstructure is in contact or near contact with the bony structure. In someembodiments, the implant may be advanced until the contact surface is incontact or near contact with the bony structure, such that at leastportion or substantially all of the truss structure is disposed in thebony structure. For example, substantially all of the struts of thetruss structure may be disposed in the slits provided in the bonystructure.

As will be appreciated, method 1900 is exemplary and is not intended tobe limiting. One or more of the elements described may be performedconcurrently, in a different order than shown, or may be omittedentirely. Method 1900 may include any number of variations. For example,in some embodiments, struts 1806 may include a sharp/thin profile suchthat minimal preparation of the bony structure needed (e.g., cuts do notneed to be provided in the bony structure) as the struts of the trussstructure may, pierce the bony structure as the implant is advanced intocontact with the bony surface. Accordingly, in some embodiments, steps1902 and 1904 of method 1900 may be combined into a single step.

In this patent, certain U.S. patents, U.S. patent applications, andother materials (e.g., articles) have been incorporated by reference.The text of such U.S. patents, U.S. patent applications, and othermaterials is, however, only incorporated by reference to the extent thatno conflict exists between such text and the other statements anddrawings set forth herein. In the event of such conflict, then any suchconflicting text in such incorporated by reference U.S. patents, U.S.patent applications, and other materials is specifically notincorporated by reference in this patent.

In accordance with the above descriptions, in various embodiments, animplant may include a web structure. The web structure for the implantmay include a micro truss design. In some embodiments, the micro trussdesign may include a web structure with multiple struts. Other webstructures are also contemplated. The web structure may extendthroughout the implant (including a central portion of the implant). Theweb structure may thus reinforce the implant along multiple planes(including internal implant load bearing) and provide increased area forbone graft fusion. The web structure may be used in implants such asspinal implants, corpectomy devices, hip replacements, kneereplacements, long bone reconstruction scaffolding, andcranio-maxifacial implants. Other implant uses are also contemplated. Insome embodiments, the web structure for the implant may include one ormore geometric objects (e.g., polyhedrons). In some embodiments, the webstructure may not include a pattern of geometrical building blocks(e.g., an irregular pattern of struts may be used in the implant). Insome embodiments, the web structure may include a triangulated webstructure including two or more tetrahedrons. A tetrahedron may includefour triangular faces in which three of the four triangles meet at eachvertex. The web structure may further include two tetrahedrons placedtogether at two adjacent faces to form a web structure with ahexahedron-shaped frame (including six faces). In some embodiments,multiple hexahedron-shaped web structures may be arranged in aside-by-side manner. The web structures may connect directly throughside vertices (e.g., two or more hexahedron-shaped web structures mayshare a vertex). In some embodiments, the web structure may be angled toprovide lordosis to the implant.

Further modifications and alternative embodiments of various aspects ofthe invention may be apparent to those skilled in the art in view ofthis description. For example, although in certain embodiments, strutshave been described and depicts as substantially straight elongatedmembers, struts may also include elongated members curved/arched alongat least a portion of their length. Accordingly, this description is tobe construed as illustrative only and is for the purpose of teachingthose skilled in the art the general manner of carrying out theinvention. It is to be understood that the forms of the invention shownand described herein are to be taken as embodiments. Elements andmaterials may be substituted for those illustrated and described herein,parts and processes may be reversed, and certain features of theinvention may be utilized independently, all as would be apparent to oneskilled in the art after having the benefit of this description of theinvention. Changes may be made in the elements described herein withoutdeparting from the spirit and scope of the invention as described in thefollowing claims. Furthermore, it is noted that the word “may” is usedthroughout this application in a permissive sense (i.e., having thepotential to, being able to), not a mandatory sense (i.e., must). Theterm “include”, and derivations thereof, mean “including, but notlimited to”. As used in this specification and the claims, the singularforms “a”, “an” and “the” include plural referents unless the contentclearly indicates otherwise. Thus, for example, reference to “a strut”includes a combination of two or more struts. The term “coupled” means“directly or indirectly connected”.

1-56. (canceled)
 57. An implant comprising: an external truss structurethat includes a plurality of planar trusses, each planar trusscomprising a plurality of struts connected to a plurality of nodes,wherein the external truss structure defines at least a side surface, atop surface, and a bottom surface of the implant; an internal webstructure enclosed by the external truss structure; wherein the internalweb structure comprises: a plurality of polar struts, wherein each ofthe polar struts of the internal web structure extends from a node ofthe external truss structure defining the bottom surface of the implantto a node of the external truss structure defining the top surface ofthe implant, and wherein each of the plurality of polar struts issubstantially perpendicular to the bottom surface of the implant andsubstantially perpendicular to the top surface of the implant; whereinthe external truss structure comprises a plurality of connecting struts,coupling ends of the polar struts to each other or connecting an end ofa polar strut to a node of the exterior truss structure, wherein atleast two of the polar struts have different lengths.
 58. The implant ofclaim 57, wherein the exterior truss structure comprises a plurality ofplanar triangular truss units having three substantially straight strutsconnected at three nodes in a triangular configuration.
 59. The implantof claim 58, wherein the planar triangular truss units are coupled toone another such that one or more planar triangular truss units lie in aplane that is not substantially parallel to a plane of a planar trussunit that shares at least one strut with an adjacent planar triangulartruss unit.
 60. The implant of claim 57, wherein at least some of theplurality of connecting struts define a side of one or more triangulartrusses, each of the defined triangular trusses having at least one nodeat an end of at least one of the polar struts.
 61. The implant of claim57, wherein one or more of the connecting struts are substantiallycurved such that the top surface and/or the bottom surface are/is asubstantially rounded surface.
 62. A method of length preservation in aseparated bone comprising: forming a contact surface on a first side ofthe separated bone; forming a contact surface on a second side of theseparated bone; placing an implant in contact with the first and secondcontact surfaces of the separated bone; wherein the implant comprises:an external truss structure that includes a plurality of planar trusses,each planar truss comprising a plurality of struts connected to aplurality of nodes, wherein the external truss structure defines atleast a side surface, a top surface, and a bottom surface of theimplant; an internal web structure enclosed by the external trussstructure; wherein the internal web structure comprises: a plurality ofpolar struts, wherein each of the polar struts of the internal webstructure extends from a node of the external truss structure definingthe bottom surface of the implant to a node of the external trussstructure defining the top surface of the implant, and wherein each ofthe plurality of polar struts is substantially perpendicular to thebottom surface of the implant and substantially perpendicular to the topsurface of the implant; wherein the external truss structure comprises aplurality of connecting struts, coupling ends of the polar struts toeach other or connecting an end of a polar strut to a node of theexterior truss structure, wherein the connecting struts partially definethe top and bottom surface of the implant, wherein at least two of thepolar struts have different lengths such that the top surface of theimplant and/or the bottom surface of the implant is/are non-planar. 63.The method of claim 62, wherein the exterior truss structure comprises aplurality of planar triangular truss units having three substantiallystraight struts connected at three nodes in a triangular configuration.64. The method of claim 63, wherein the planar triangular truss unitsare coupled to one another such that one or more planar triangular trussunits lie in a plane that is not substantially parallel to a plane of aplanar truss unit that shares at least one strut with an adjacent planartriangular truss unit.
 65. The method of claim 62, wherein at least someof the plurality of connecting struts define a side of one or moretriangular trusses, each of the defined triangular trusses having atleast one node at an end of at least one of the polar struts.
 66. Themethod of claim 62, wherein one or more of the connecting struts aresubstantially curved such that the top surface and/or the bottom surfaceare/is a substantially rounded surface.